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tween the pterapophyses' of the sphenoid: the dimension is two inches five lines. In the 
Dinornis and Palapteryx, the lower point of the compass in this measurement touches 
the narrow presphenoidal prolongation of the sphenoid, and the dimension does not 
exceed two inches. Asa result of this anterior production of the frontal, it overhangs in 
a peculiar degree the coalesced prefrontals which are excavated to form the wide cham- 
bers of the olfactory capsules, and the upper walls of which chambers coalesce with the 
overarching part of the frontal. 
The cranium, Pl. LIII, fig. 6, exhibits in a remarkably perfect degree the three 
transverse processes (4,8, 12) of the three principal vertebre of the skull, together with 
the basisphenoidal platform and the pterapophyses (s’) of the sphenoid. This appears 
to be of the same species as the more mutilated cranium figured in Pl. XLVI. 
figs. 4 & 5. The paroccipitals (4) are less expanded relatively than in the Pal. 
ingens, and are almost straight vertical plates. The apophysary part of the mastoid (8) 
is also vertical, straight, and compressed from behind forwards with the outer border a 
little advanced. Between this and the postfrontal intervenes a wide and deep temporal 
fossa, much exceeding in its proportional size that of the Palapteryzx figured in Pl. XLV. 
fig. l. The postfrontal (12) is long, three-sided, and curves outwards, downwards and 
backwards as low down as the mastoid. The pterapophyses (s') are shorter than in the 
Ostrich or Emeu, and are depressed. The base of the alisphenoid swells out a little 
above them. 
The cranium, Pl, LIIL. fig. 5, is somewhat smaller than that of the Palapteryx figured 
in Pl, XLV.; it more nearly corresponds in size with that figured in Pl. XLVI. 
fig. 3, but it differs in the greater elevation of the frontal region, which is more marked 
than in any skull of Dinornis or Palapteryx I have yet seen. ‘This skull is of a mature 
bird: all the cranial sutures are obliterated ; and we learn from the specimen of the 
young Dinornis, Pl. LIII. fig. 2, that, as in the Ostrich, this obliteration did not take 
place in these wingless birds until they had nearly arrived at their full size, 
The interorbital part of the skull is relatively narrower than in the Palapteryx 
(Pl. XLV.): the temporal fossz are relatively narrower than in the skull, Pl. LIIT. fig. 6. 
The oevipital condyle is more sessile than in the larger species, and the occipital 
foramen is less vertical, the plane sloping from above downwards and a little forwards. 
The mastoid is shorter and more pointed, and the pneumatic hole is reduced to a very 
small foramen behind its base. The interorbital septum is entire and thick; a slender 
compressed process (Pl, LITT. fig. 5, 12) is sent down from it just behind the large olfac- 
tory fossa. The cranial end of the premaxillary, which is bifid as in the Ostrich, has 
coalesced with the frontal; but they remain distinct from the subjacent prefrontals, 
which have as usual coalesced together to form the cavities for the olfactory capsules. 
The septum between these cavities is entire, 
' L use this word instead of ‘pterygoid processes,’ as the latter term has been employed in Anthropotomy to 
designate the independent bones, called ‘ pterygoids,’ which, in birds, articulate with the pterapophyses. 


